Method and system for optimizing performance of a mobile communication system

ABSTRACT

Call data collected from the switch at a Mobile Telephone Switching Office is combined with location information of a mobile unit to generate information reports concerning the electromagnetic coverage of a geographic region. The collection of call data from the switch permits consideration of uplink information in the analysis of system performance. The uplink information reflects performance of specific equipment that is in use by the wireless customer. This uplink information may be combined with downlink and location information to remove from the performance evaluation transient effects associated with, for example, local terrain and other physical impairments.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to mobile communications systems and, morespecifically, to a method and system for optimizing performance of amobile communications system.

2. Background of the Invention

FIG. 1 shows a block diagram of a conventional cellular radiotelephonecommunication system 5 which includes cells 6, radio base stations orcell sites 8, and a Mobile Telephone Switching Office (MTSO) or mobiletelephone switching center 9. As a mobile telephone customer 7 movesfrom one cell to another a switch in the MTSO automatically switchesconnections with the respective radio base stations to maintain acontinuous connection with the public switched network (not shown).Typically, a switch in an MTSO 9 is connected to approximately onehundred cell sites.

A problem associated with the management of a cellular radiotelephonecommunications system is geographically locating an area within the zoneof radio coverage or cell where faulty coverage exists. An example wouldbe an area within a cellular telephone system that provides poor servicedue to moderate levels of interference. Typically, this situation isuncovered in one of two ways; customer complaints or the persistentdrive team testing by system operators. Neither of these approaches,however, provides a very timely or comprehensive means of identifying,diagnosing, and curing faulty coverage.

In response to these deficiencies, the cellular industry has turned tothe aid of electromagnetic coverage prediction tools to assist in thesearch for holes in the coverage. Typically, these methods of monitoringsystem performance include observing downlink information along withother system parameters. (Downlink being defined as signals travellingfrom the cell site to the mobile unit and uplink being defined assignals travelling from the mobile unit to the cell site). Theassumption has been that if the downlink was closed (i.e., a goodconnection was attained), the available uplink power would be sufficientto close the uplink.

One such electromagnetic coverage tool which takes into account uplinkinformation is discussed by Kurt Nikkinen in “Switch Reality”, AT&TWireless Service, Apr. 15-16, 1997, and hereby incorporated byreference. This electromagnetic coverage tool involves transmittinglocation information of a mobile unit to a base station using a cellularmodem and also gathering call information from a switch location. Thelocation and call information is then collected at the base station andentered into a map plot.

SUMMARY OF THE INVENTION

The present invention is briefly described as a method and system ofmonitoring the performance of a wireless telecommunications system. Inpreferred embodiments there is disclosed a method and system ofevaluating the coverage of a geographic area serviced by a mobilecommunications system.

In one aspect, the method includes obtaining uplink performanceparameters related to at least one mobile unit from the mobile switchingcenter, obtaining location information related to the location of themobile unit, and analyzing the performance of the telecommunicationssystem based on the uplink and downlink performance parameters and thelocation information to obtain analysis results.

In one aspect, the system includes monitoring performance of a wirelesstelecommunications system, the system including: a mobile unit forming awireless connection to a radio base station; the radio base stationconnected to a switch; a base system analyzer coupled to said switch andwhich performs analysis of call data collected at the switch; a mobilePC transmitting location over a packet network to the base systemanalyzer; and wherein the system analyzer evaluates the performance ofthe telecommunications system based on uplink performance parameters andthe location of the mobile unit.

In one aspect, the system includes monitoring performance of a wirelesstelecommunications system, the system including: a mobile unit forming awireless connection to a switch; a means for collecting and transmittinguplink performance parameters of the wireless connection at the switchto a system analyzer; a means for sending the location of the mobileunit to the system analyzer; and wherein the system analyzer evaluatesthe performance of the telecommunications system based on the uplinkperformance parameters and the location of the mobile unit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a conventional cellular radiotelephonesystem;

FIG. 2 is a block diagram of a system for optimizing a mobilecommunication system according to a preferred embodiment of the presentinvention in which location data of a mobile unit is sent over a packetnetwork such as a cellular digital packet data (CDPD) network;

FIG. 3 is a block diagram of a system for optimizing a mobilecommunication system according to an alternative embodiment of thepresent invention In which the location data in maintained at the mobileunit and call data is sent over a packet network (e.g., CDPD network)from the switch to a mobile PC with GPS which is acting as the basestation;

FIG. 4 illustrates a suite of software programs that will be used in themethod and system of the preferred embodiment;

FIG. 5 illustrates a visual CER display on a base PC;

FIG. 6 illustrates a Visual GPS display on a mobile PC with GPS;

FIG. 7 illustrates a Mapview display on the base PC;

FIG. 8 illustrates a flowchart demonstrating how the Visual CER programoperates;

FIG. 9 illustrates a flowchart demonstrating how the Visual GPS programoperates; and

FIGS. 10A-10L Illustrate how the Mapview program operates.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

In the preferred embodiment, call data collected from the switch at theMobile Telephone Switching office (MTSO) or mobile switching center iscombined with location information of a mobile unit to generateinformation reports concerning the signal coverage of a geographicregion. The collection of call data from the switch at the switchingcenter permits consideration of uplink and also downlink information inthe analysis of system performance. The uplink information reflectsperformance of specific equipment that is currently in use by thewireless customer. This uplink information may be combined with locationinformation to remove from the performance evaluation transient effectsassociated with, for example, local terrain and other physicalimpairments. The preferred embodiment also allows real-time analysis tobe performed by transmitting data over a packet network such as acellular digital packet data (CDPD) network.

FIG. 2 is a diagram of a communication system 10 employing a preferredembodiment of the present invention. Since it is understood by thoseskilled in the art that other components and devices are typicallyincluded in this environment, only those pertinent to the preferredembodiment will be discussed.

Mobile vehicle 11 contains a mobile unit or station 12 and a mobilePersonal Computer with a Global Positioning System (PC/GPs) 14. The GPSallows the location of the mobile unit to be monitored with highaccuracy. The GPS used in the PC/GPS 14 may be a TRIMBLE PCMCIA GPSreceiver. The mobile unit 12 may include cellular telephones, personalcodification system (PCS) handsets, or some other type of mobilecommunication device not limited to telephones such as personalcomputers, paging devices, etc. In this discussion, cellular is beingused to indicate any type of mobile communication system—analog ordigital—which divides a region into geographic areas (cells) andinvolves handing off of the mobile unit as it moves from cell to cell.PCS is a type of cellular mobile communication system which is digitallybased and therefore can offer a broader range of services than an analogbased system. Although any type of mobile communication device may beused as the mobile unit 12, the use of a digital device would providethe most information.

As the mobile unit 12 moves through the cellular system it operates offof cell sites connected to local voice switches. The mobile unit 12transmits voice calls to a receiver 17 at a radio base station (RBS) 16through a transmitter 13. (Alternative embodiments may have a greaternumber of transmitters and receivers). The call is then routed through astandard link 19A to a local voice data network switch 18 connected tothe RBS 16. The call data is collected at the voice switch 18 andforwarded over a standard link 19B such as a Local Area Network (LAN) orvoice line to the base unit 23. (Note that in an alternative embodimentlink 193 may be a CDPD network). The base unit 23 contains a base PC 22and a CDPD modem 22A. The PC 22 functions as a system analyzer foranalyzing the incoming data.

In the preferred embodiment, the call data is collected on the uplink atthe switch 18 using Cell Traffic Recording (CER) software. CER is asoftware function provided to users of an Ericsson mobile telephoneswitch. CER describes everything about the call in text format. Thisfunction allows real-time tracing of the activities of a phone call inprogress. Although the preferred embodiment is directed to an Ericssonswitch the invention may just as well involve other switches usingsoftware other than CER to collect call data. The call data is routedfrom the switch 18 in serial text format to the PC 22 at the base unit23.

The call data collected from the switch 18 may include many differenttypes of mobile communication system parameters. Examples include, butare not limited to, the following: Forward and Reverse (or Received)Signal Strength Indication (SSI); Forward and Reverse Bit Error Rate(BER); Time Alignment; Frequency error: Power Level of Mobile (PLM)unit; Frequency Group; Channel; Voice Channel Group; Mobile DeviceIdentification Number; Mobile Manufacturer Information; and MobileAssisted Handoff (MAHO) information which may include data onneighboring cell sites as well.

Therefore, the preferred embodiment allows a system evaluator located atthe base PC 22 to take advantage of information from the switch toanalyze the service provided by the cell. The preferred embodimentallows two types of analysis to be performed. The first one is areal-time analysis which occurs while the mobile unit 12 is traversingthe drive route. The real-time nature of the analysis allows the systemevaluator located at the base PC 22 to be in communication with thedriver located in the mobile vehicle 11 and to receive constant reportsfrom the driver on obstacles which might be the cause of problems in theservice (i.e., tall buildings, mountains, etc.). The second type ofanalysis is post-processing analysis which occurs after the driver hascompleted traversing the route. The second type of analysis is morein-depth and allows the call data and location data to be recorded andthen analyzed in many different ways to optimize the service level ofthe cell site.

Collecting call data at the switch allows, for example, analysis ofinformation such as the mobile assisted handoff (MAHO) received signalstrength indicator (RSSI) of the neighboring cells reported back to thevoice switch 18 by the mobile unit 12. MAHO is the method that enablesthe hand-off from cell site to cell site to be triggered using thedownlink signal strengths of a measurement channel. Therefore, the voiceswitch 18 maintains which cell is carrying the call and it also has alist of neighboring cell sites that are to be considered as handoffcandidates. The neighbor list includes the measurement channel, usuallythe digital control channel (DCCH), associated with a neighboring cell.The voice switch 18 sends a list of measurement channels to the mobileunit 12 to be scanned. The measurement channel is continuouslytransmitting a downlink signal that the mobile unit 12 records the RSSIlevel of and every second reports back the RSSI levels of theneighboring cells from the list to the voice switch 18. When aneighboring cell becomes the better server, a hand-off will take place.The switch 18 at the MTSO determines when to hand the mobile customeroff. By recording these MAHO RSSI values the preferred embodiment isable to provide a very complete picture of the coverage area of theserving cell as well as all of its neighboring sites in the systemanalysis step which will be discussed below. This way more detailedcoverage plots may be obtained with only one drive test.

The call data from the switch 18 contains almost all of the importantinformation about the parameters of a call but cannot provide thecurrent location of the mobile customer to determine where a problem incoverage is occurring. So the information is irrelevant if the locationof the mobile unit 12 cannot be found.

Messages concerning the current location (i.e, latitude and longitude)of the mobile vehicle 11 with the mobile unit 12 are sent from PC/GPS 14through a transmitter 15 and are received at cellular digital packetdata (CDPD) network equipment 16A located at RBS 16 as shown in FIG. 2.CDPD is a technology that folds data into packets that are sent at veryhigh speeds during pauses in cellular phone conversations. By addingCDPD technology to an existing cellular system, the location data may besent without congesting voice channels with data.

The location data is sent from the RBS 16 over a CDPD network 28 to adata network switch 20. The data network switch 20 then connects toanother RBS 25 through a link 29. The RBS 25 sends the information fromantenna 25A to the CDPD modem 22A of the base station 23. At PC 22 inthe base station 23, the location information and the call data arecombined and analyzed to evaluate the system performance. The use of theCDPD network 28 allows the location information to be sent to the basePC 22 even if the voice network has failed and thereby improving thereal-time nature of the analysis.

Another aspect of the preferred embodiment is that the location data mayalso be stored locally on the mobile PC/GPS 14 with a time stampsynchronized with the central location PC 22 in case the CDPD network isdown. Therefore, although the real-time nature of the analysis is lost,the test drive of the vehicle 11 may be recorded and evaluated in apost-processing time period.

Another aspect of the preferred embodiment is that by allowing thePC/GPS 14 to deliver the location data over the CDPD network it allowsthe testing of the CDPD network at the same time. If the systemevaluator does not see the vehicle's 11 position on the central locationor base PC 22 then the CDPD network is not working in that area and aCDPD technician may be dispatched to investigate.

Another aspect of the preferred embodiment is that the central location23 may be located right at the switch 18 or at any other location toobtain even greater efficiency.

The system analysis of the preferred embodiment is conducted at the basePC 23. As previously discussed, the preferred embodiment allows forreal-time analysis as well as post-processing analysis to occur. Thepreferred embodiment involves merging the call data information from theuplink at the switch 18 with the location of the mobile vehicle 11 anddownlink information to produce and display a map to diagnose how thesystem is performing as the mobile vehicle 11 drives around. Thisinformation is used to fine tune the cellular network. By using the calldata information from the switch 18 it allows a system evaluator toexamine both the quality of the uplink and the downlink and correct anyproblems found. For example, by analyzing the data it may be found thatthe mobile unit 12 may not be powering up enough and it should bepowered up more.

In an alternative embodiment shown in FIG. 3, a communication system 20is shown in which call data is collected at the switch 18 and sent overthe CDPD network 28 back to the mobile vehicle 11 and merged with theGPS location data on the mobile PC/GPS 14. The real-time analysis couldthen be done at the mobile vehicle 11 instead of on the base PC 22 atthe central location 23. The mobile unit 12 may be used because themobile unit does not have to be connected to the PC/GPS 14. Thisalternative embodiment would allow the system evaluator conducting thedrive test to monitor the call data while seeing for himself thesurrounding topography. The system evaluator may then remove from theperformance evaluation transient effects associated with, for example,local terrain and other physical impairments.

In the preferred embodiment, the system analysis is primarilyaccomplished through a suite of optimization software programs 40 asdisclosed in FIG. 4. The optimization software programs 40 provide a wayto efficiently optimize telephone systems in both real-time whileidentifying service interruptions and also in a post-processing timeperiod for more in-depth analysis. The optimization system software 40as shown in FIG. 4 includes MICROSOFT WINDOWS 95™ 42, a system parser44, a master database 46, REFLECTIONS TCP/IP (transmission controlprotocol/Internet protocol) 48, Visual CER 50, visual GPS 52, Mapviewsoftware 54, and a location database 56. The optimization systemsoftware 40 may be loaded on the base PC 22 and the PC/GPS 14. Note thatthe optimization system software 30 is not limited to these softwareprograms and may include more software programs and/or different typesdepending on the type of coverage analysis required.

Windows 95™ 42 is a well-known Microsoft™ product which may be used asthe operating system.

The system parser 44 is a software program that utilizes data which iscollected from the switch 18 and from other sources to update the mastersystem database 46. The system parser 44 may be used to convert textfiles in ASCII form collected from the switch 18 into tables. Thesetables are then joined into relations to provide queries to bevisualized later in the optimization process.

The master database 46 may be implemented Using Microsoft™ Access™ inthe preferred embodiment. The master database 46 is utilized as thecentral point for all system information. The master database 46 is madeup of mapable tables which are being constantly updated by the systemparser program 44. These mapable tables are used by the Visual CER 50,Visual GPS 52, and Mapview 54 programs to geographically display theswitch and cell information. The multiple tables in the master database46 reflect the actual switch 18 parameter settings and other data aboutthe cellular network. Visual CER 50 and Mapview 54 use the masterdatabase 46 so that what is seen on their maps is what is really in theswitch 18. This allows the system evaluator to find problems andtherefore quickly improving the performance of the network and thusreduce the number of customer complaints.

One of the most overlooked aspects of maintaining a cellular telephonenetwork is the maintenance of the system databases. Most are staticdatabases containing information about site locations, antennas,transmission lines, tower heights, FAA information, etc. The databasesthat contain information about the parameters that control how themobile acts while in the network are more variable. When theseparameters are changed in the switch 18 and are not updated in thesystem parameter waster database 46, the system operators may be makingdecisions with incorrect data resulting in lost time and poor results.Therefore, an advantage of the preferred embodiment is that the softwareprograms used in the system analysis allow the system evaluator to relyon constantly updated information from the switch 18.

Two software programs which may be used for data collection andreal-time vehicle position tracking at both PC/GPS 14 and PC 22 includeVisual CER 50 and Visual GPS 52. A typical PC screen display of VisualCER 50 is shown in FIG. 5 and a typical PC screen display of Visual GPS52 is shown in FIG. 6. Both Visual CER 50 and Visual GPS 52 in apreferred implementation are software programs written using Microsoft'sVisual Basic™. Visual CER 50 in the preferred embodiment is loaded intothe base PC 22 to allow for real-time observation of the call datacombined with the location information of the mobile vehicle 11. VisualGPS 52 is loaded into the PC/GPS 14 and allows the operator of thevehicle 11 to observe the location of the vehicle 11 on the PC/GPS 14.As previously discussed, the Visual GPS program 52 will transmit thelocation data to the base PC 22 through the CDPD network 28. The PC/GPS14 may also record the location data along with a base/remotesynchronized PC time stamp to the location database 56 for later use. Asdiscussed above, a base/remote synchronized PC time stamp is sent frombase PC 22 to PC/GPS 14 so that the recording of data in both locationsis synchronized for post-processing system evaluation. The Visual CERprogram 50 will merge the call data from the switch 18 with the locationdata received from the mobile unit 12. This composite information isthen logged and displayed in real-time for the System evaluator at thebase PC 22.

FIG. 8 illustrates the operation of the Visual CER program 50. In step802, the database and streets map are loaded in the base PC 22. In step804, a Visual CER form and a street map are displayed. In step 806, themobile phone Internet Protocol (IP) address is received via the CDPDnetwork and the vehicle location is calculated and displayed. Inoptional step 808, the mobile phone number to be recorded may bechanged. In optional step 810, the recording object group parameters maybe changed. The recording object group parameters are the parametersthat dictate the length of the CER recording and a list of mobile phonenumbers that the system evaluator wants to record. In step 812, a choiceis made whether to quit or record the drive. It the decision is made toquit, then in step 814, the database of the PC 22 is unloaded. If thedecision is made to record the drive, then step 816.

In step 818, the PC time stamp is sent from the base PC 22 to the PC/GPS14 via the CDPD network. In step 820, the mobile unit 12 is called tostart the flow of call (or CER) data at the switch 18. In step 822, thecommunication port on the base PC 22 is checked for call data from theswitch 18. In step 824, it is determined if data has arrived. If no datahas arrived, then the CDPD data is read and a new position of thevehicle 11 is calculated in step 826. The updated position is thendisplayed on the base PC 22 in step 836 and then a loop back occurs tostep 822 to check the confiscation port again.

If call data has arrived in step 824, then the decision is made to go tostep 828 and read and display call data on the base PC 22. In step 830,the CDPD data is read and the new vehicle position is calculated. Instep 832, CER call data is merged with vehicle position data. (Themerger is synchronized based on the time stamp which was sent to thePC/GPS 14 in step 818). In step 834, the merged data is written into themaster database 46. In step 836, the updated vehicle position isdisplayed and then the decision is made to go to step 822 to check thecommunication port again for more data.

Referring to FIG. 9, the Visual GPS program 52 is loaded into PC/GPS 14.In step 902, the cell site database and streets map is loaded. In step904, a Visual GPS form and street map are loaded. In step 906, the basePC 22 IP address is loaded. In step 908, mobile PC/GPS 14 IP address issent to base PC 22 via CDPD network. In step 910, the vehicle positionis calculated and displayed on a Visual GPS map. In step 912, thedecision is made to quit (and unload the database in step 916) or waitfor a received time stamp message from the base PC 22. In step 914, ifthe set time message has not arrived the Visual GPS program will loopback to step 910. If the time stamp message has arrived, the Visual GPSprogram will proceed to step 918 to synchronize the mobile PC/GPS 14time with the base PC 22 time, In step 920, the communication port onthe PC/GPS 14 will be checked for location data from the GPS receiver.In step 922, if location data has not arrived, then the decision is madeto go to step 924 and check for GPS error. It there is an error, the GPSreceiver is reset and the decision is made to go to step 920 and ifthere is no error the decision is made to go to step 920. If locationdata is received in step 922, then calculate vehicle position in step926. Send GPS data and mobile time stamp to base PC via CDPD network instep 928. In step 930, write data into Visual GPS location database 56.In step 932, display updated vehicle position on Visual GPS map and thenreturn to step 920.

The Mapview software 54 (“Mapview”) will be used in the preferredembodiment for in-depth, post-processing evaluation of the call data andlocation data obtained from the mobile vehicle 11. The Mapview softwarein a preferred implementation is written using Microsoft Visual Basic™and also utilizing Mapinfo™ software. The Mapinfo™ software may be usedas a geographical object in Mapview 54 displaying a preconstructedworkspace consisting of a sector and street map. In a preferredimplementation the Mapview software 54 is loaded on the base PC 22.However, in the alternative embodiment discussed with respect to FIG. 3the Mapview software 54 may be loaded on PC/GPS 14 and thepost-processing performed at the mobile vehicle 11.

A typical PC screen display of Mapview 54 is shown in FIG. 7. TheMapview program 54 is used to simultaneously view graphically on thebase PC 22 the information contained within the master database 46 aswell as the drive test data collected using Visual CER 50 and Visual GPS52, and customer complaints from a trouble tracker system used by acustomer care department. By placing the drive test data within anaccurate network environment, Mapview 54 allows the system evaluator toquickly identify the problem areas and diagnose the cause. By overlayingthe customer complaints the system evaluator may determine future driveroutes that will be driven and document network improvements.

A problem in maintaining a cell network is maintaining the systemdatabases for frequency planning, hand-off parameters, and accessparameters. The optimization software 40 uses the master database 46which is updated from data files pulled from the switch 18. By updatingthe master database 46 from switch ASCII log files it helps eliminateerrors due to human mistakes. The master database 46 has severalpredefined queries that provide the system evaluator with accurate voicechannel counts, accurate frequency information, and a means to evaluateand track system parameter changes. This data is then automaticallyconverted into color coded maps using Mapview 54 with respect to thesites geographic location for easy problem detection which saves timeand resources.

Mapview 54 generates at least 10 drive test exception plots. Theyinclude SSFVC (signal strength forward voice channel), FBER (forward (ordownlink) bit error rate), SSRVC (signal strength reverse voicechannel), RBER (reverse (or uplink) bit error rate), PLM (mobile RFpower level), Path Delta (which identifies uplink/downlink RSSIdifferences), BSVR Delta (which indicates when the mobile is not on thebest strongest site), HANDOFFS (identifies intercell handoffs, intracellhandoffs (interference), and interexchange handoffs (handoffs acrossswitch borders)), DROPS (identifies dropped calls), and MOBILE GROUPS(frequency group that the mobile is on). To make obtaining these plotsas easy as possible Mapview 54 has a benchmark option that will generatea complete set of these plots if selected. All of these plots areexception plots which means that only the problems are highlighted. Allof the thresholds are preset ensuring that all of the system engineersare using the same values.

With Mapview 54, the system evaluator can display the relative networkinformation dealing with a specific problem that is attempted to besolved. Mapview 54 will display the following information: locations foractive and/or proposed cells, customer complaints by type, frequencygroups (digital and analog), SAT (supervisory audio tone), and DCC(digital color code) information, paging and location areas (used forcall delivery), and voice channel handling selection order. By selectinga particular sector the system evaluator may view detailed informationabout that sector including the individual channels associated to thatsector.

FIG. 10A illustrates a Mapview flowchart describing a preferredimplementation. In step 1002, all device tables are loaded in the basePC 22. In step 1004, all thematic maps are loaded. Thematic maps arecolor coded maps based on temperature schemes (i.e., red being hottestor weak signal, yellow being mild, blue being coldest or good signal) toindicate troubled coverage areas. In step 1006, the Mapview main form isdisplayed. In step 1008, the next operation is chosen by the systemevaluator depending on what area type of analysis he wants to perform.

FIG. 10B illustrates path A which allows the operator to work with filecommands 1010. The operator may open a file 1012 which includes newfiles 1014, tables 1016, open databases (OD) 1018, workspace 1020,traffic 1022, CER data 1024, and complaints 1029. CER data 1024 includesnew CER data 1026 and appended CER data 1028 (which is a combination ofCER data files). The system evaluator may also save 1030 map files undernew 1032, table 1034, OD 1036, and workspace 1038. The operator may alsoprint a map 1040, benchmark an entire drive test 1042 (prints all thedifferent types of maps automatically), or exit the program 1044.

FIG. 10C illustrates path B which allows the operate to create athematic map of cells 1046. The cells could include active cells 1048 orproposed cells 1050. Legend 1052 is used in Mapview 54 to displaysymbols and is used here in the same manner as the term “legend” is usedin a street map.

FIG. 10D illustrates path C which creates a thematic map of specificevents recorded during a Visual CER drive test 1054. The events asdiscussed above include PLM 1056 (power level at the mobile unit 12),SSFVC 1058, FBER 1060, SSRVC 1062, RBER 1064, Audio Q 1066 (AudioQuality), Handoffs 1068, Dropped Calls 1070, BSVR Delta 1072, Path Delta1074 (difference between forward and reverse signal strength). MobileC/I 1076 (mobile carrier interference ratio), Mobile SAT 1079 (mobilesupervisory audio tones), Mobile Groups 1080, and legend 1082.

FIG. 10E illustrates path D which creates a thematic map from anytrouble tracker or complaint database file 1084, The complaints includeaudio 1086, service 1088, dropped calls 1090, interference 1092, othertypes 1094, composite 109E (a collection of different types ofcomplaints), and Legend 1098.

FIG. 10F illustrates path E which creates a thematic map from anytraffic file 1100. The traffic file includes Ccong 1102 (congestion), MHTime 1104 (mean holdtime), Erlangs 2106 (measurement of call seconds),and Legend 1108.

FIG. 10G illustrates path F which creates a thematic map from visual CERcollected drive test data 1110. The drive test data include SAT 1112(supervisory audio tones), RF power settings 1114, or antenna patterns1116. Playback 1118 of the drive test data is also included.

FIG. 10H illustrates path G which selects the modulation mode 1120 forall views to be displayed. The modes include CDPD 1122, analog 1124, anddigital 1126.

FIG. 10I illustrates path H which creates a thematic map representingthe frequency groups 1130 and/or color codes 1140 assigned to all of thecell sites. Frequency groups 1130 include for example Sector A 1132,Sector B 1134, Sector C 1136, or all three Sectors 1138 which make upthe 360 degrees of direction of a cell site.

FIG. 10J illustrates path I which allows removal of selected map layers1152. The settings include None 1154, Active 1156, Proposed 1158,Traffic 1160, Groups 1162, CER data 1164, Network 1166, and complaints1168.

FIG. 10K illustrates path J which assigns curser tools that performindependent tasks 1170 in the map in Mapview 54. The tools include Edit1172, Redraw 1198, Grabber 1200 (which allows the system evaluator tograb the map and move it to a new location), Pointer 1202, InformationTool 1204, Ruler 1206 (allows measurements between points in cellsites), Label 1208, Zoom in 1214, and Zoom Out 1216. The Edit tool 1172allows for cutting 1174, copying 1176, drawing 1178, and select 1188.Drawing 1178 includes lines 1180, polygonal lines 1182, points 1184, andpolygons 1186. Select 1188 includes a bin 1190, a polygon 1192, a circle1194, and a calculate function 1196. The Label tool 1208 includesstreets 1210 and servers 1212.

FIG. 10L creates a thematic map representing the network paging locationarea assignments 1218. Assignments include MEP 1220 which includes localareas 1222 and Legend 1224. This allows for a more efficient pagingmethod by limiting the number of cell sites that have to be paged.

Based on the mobile communications system analysis, adjustment way bemade to one or all of the system parameters to obtain optimumperformance. For example, adjustments include changing the down tilt ofthe RBS antenna 17 (to take energy off horizon so as to concentrate it)or increasing or decreasing the power of a cell site. System evaluatorshave agreed on certain goals that must be achieved by the systemparameters such as a specific set of RSSI level break points, BERthresholds forward and reverse, etc., that are a requirement for a cellsite. The mobile communications system analysis of the preferredembodiment may be used to expedite service improvements and to determinefuture build plans.

The above-described embodiment is illustrative of the principles of thepresent invention. Various modifications and changes may be devised bythose skilled in the art without departing from the spirit and scope ofthe invention as set forth in the appended claims.

What is claimed is:
 1. A method comprising: receiving at a cell site awireless signal from a mobile wireless system; determining at least oneof signal strength and signal error of the wireless signal;communicating the at least one of signal strength and signal error tothe mobile wireless system; the mobile wireless system correlating theat least one of signal strength and signal error with locationinformation collected by the mobile wireless system; communicating theat least one of signal strength and signal error through a data switchbefore communicating the at least one of signal strength and signalerror to the mobile wireless system, wherein the data switch is part ofa cellular digital packet data (CDPD) network; and communicating the atleast one of signal strength and signal error through a voice switchbefore communicating the at least one of signal strength and signalerror to the mobile wireless system.
 2. A method comprising: receivingat a cell site a wireless signal comprising location data from a mobilewireless system, the location data received via a voice channel;determining at least one of a signal strength and signal error for thewireless signal; communicating the at least one of a signal strength andsignal error to a processing device via a voice switch; communicatingthe location data to the processing device via a data switch; and theprocessing device causing the at least one of a signal strength andsignal error to be visually correlated with the location data.
 3. Themethod of claim 2, further comprising: communicating the at least one ofa signal strength and signal error to the processing device in a firstbase station; communicating the location data to a second base station;and the second base station communicating the location data to the firstbase station.
 4. The method of claim 3, further comprising: the secondbase station communicating with the first base station via a CDPD modem.5. The method of claim 2 wherein the location data is received via CDPD.